Artificial tongue may help build better chocolate

Few can deny that one of life’s greatest gustatory pleasures is that first silky smooth release of fat, sugar and cocoa that comes after biting into a favourite piece of chocolate.

While many of us might prefer to keep this sensation in the realm of culinary magic, scientists aren’t usually content until they untangle the “how” and the “why” of things.

So, using an artificial tongue and a few pieces of high-end chocolate, that’s what researchers at the University of Leeds (UL) in the UK have done. They say the chocolate pleasure principle all comes down to when the fat is released and indicate that the discovery could lead to the development of a healthier chocolate bar that still delivers all the joy.

In their quest to take all the fun out of eating chocolate … er, rather – to find out just how chocolate’s ability to coat our mouths in all its glory actually works – UL researchers got ahold of four dark chocolate samples of Lindt Excellence bars containing between 70-99% cocoa. They then set out to examine the chocolate’s “frictional behaviour.”

To do so, they placed the chocolate on an artificial tongue developed at the university in 2020. While we’ve seen artificial tongues sense the difference between whiskys, wines, beers, and evaluate the sweetness of chamomile tea and apple juice, the researchers say their study marks the first time such a technology was used to understand how chocolate lubricates the mouth.

After the different chocolates were placed on the artificial tongue, the researchers imaged the results and used a field of engineering called tribology, which concerns itself with how surfaces and fluids interact with each other, to understand the treat’s behavior as it melts and interacts with saliva.

They discovered that the satisfying silky sensation that chocolate provides in the mouth is due to the initial release of fat on the tongue and the way in which subsequent cocoa particles are coated in fat.

After that, additional fat deeper in the chocolate bar had a limited impact on the mouthfeel. Therefore, the researchers say, it could be possible to create a chocolate bar that has its fat concentrated largely on the outside of the bar and around the cocoa particles with less fat overall inside, which would make for a healthier treat.

“With the understanding of the physical mechanisms that happen as people eat chocolate, we believe that a next generation of chocolate can be developed that offers the feel and sensation of high-fat chocolate yet is a healthier choice,” said study lead Siavash Soltanahmadi, from the UL’s School of Food Science and Nutrition.

“Our research opens the possibility that manufacturers can intelligently design dark chocolate to reduce the overall fat content. We believe dark chocolate can be produced in a gradient-layered architecture with fat covering the surface of chocolates and particles to offer the sought after self-indulging experience without adding too much fat inside the body of the chocolate.”

The research has been published in the journal ACS Applied Materials & Interfaces.

Source: University of Leeds via Eurekalert